The present invention is a connector used in wood frame construction and most specifically relates to those devices known as holdowns. Holdowns, as the term is used in the building construction industry refer to those metal connectors which tie the wood framing studs to the concrete foundation. Holdowns are to be distinguished from mudsill anchors which connect only the wood mudsills to the concrete slab or foundation walls. Holdowns are necessary in areas subject to earthquakes, hurricanes and typhoons. The standard practice of simply nailing studs to the mudsill is inadequate to anchor the building to its foundation. Holdowns are connected to the studs by bolts and are attached to the foundation by bolts anchored in the concrete.
Prior to the present invention, all holdowns were constructed from heavy gauge metal, welded and then painted. The hand labor in the welding and painting operations made mass production slow and relatively costly. Examples of welded holdowns as presently used in the construction industry are shown in Simpson Strong-Tie Connectors for Wood Construction, January 1985, Catalog 85H-1, Page 7. The HD 2 and HD 5 holdowns are shown and discussed in Gilb, U.S. Pat. No. 4,192,118, granted Mar. 11, 1980 which patented the HDN series. The HD 9 is the subject of U.S. patent application, Gilb, Ser. No. 567,357 filed Dec. 29, 1983, now abandoned. The HD 6 is protected by U.S. Pat. No. Des. 224,083 granted July 4, 1972.
Another important aspect of the prior art holdowns is the fact that all of them are attached to threaded bolts in which the stand off distance between the underside of the seat and the top of the mudsill varies between 11/2 to 3 inches. This stand off distance results from a building code requirement which requires a distance of 7 bolt diameters from the center of the lowest bolt opening in the back of the holdown to the top of the mudsill. Since the holdown is constructed from heavy gauge metal, it is standard practice to reduce the weight of the holdown by either terminating the member at the seat or providing a depending foot below the seat to provide self jigging of the device for installation.
Finally, while all connector manufacturers make numerous connectors such as hangers, anchors and straps from galvanized sheet metal, none of them manufacture a holdown made from sheet metal. Thus, fabrication techniques and painting have added significantly to the cost of manufacture of the present heavy gauge welded and painted holdowns.